Overcoming the rare species modelling paradox: test of a novel hierarchical framework with an Iberian endemic plant

Rare species have restricted geographic ranges, habitat specialization, and/or small population sizes. Datasets on rare species distribution usually have few observations, limited spatial accuracy and lack of valid absences; conversely they provide comprehensive views of species distributions allowing to realistically capture most of their realized environmental niche. Rare species are the most in need of predictive distribution modelling but also the most difficult to model. We refer to this contrast as the "rare species modelling paradox" and propose as a solution developing modelling approaches that deal with a sufficiently large set of predictors, ensuring that statistical models aren't overfitted. Our novel approach fulfils this condition by fitting a large number of bivariate models and averaging them with a weighted ensemble approach. We further propose that this ensemble forecasting is conducted within a hierarchic multi-scale framework. We present two ensemble models for a test species, one at regional and one at local scale, each based on the combination of 630 models. In both cases, we obtained excellent spatial projections, unusual when modelling rare species. Model results highlight, from a statistically sound approach, the effects of multiple drivers in a same modelling framework and at two distinct scales. From this added information, regional models can support accurate forecasts of range dynamics under climate change scenarios, whereas local models allow the assessment of isolated or synergistic impacts of changes in multiple predictors. This novel framework provides a baseline for adaptive conservation, management and monitoring of rare species at distinct spatial and temporal scales.

Updating and validating the Charlson comorbidity index and score for risk adjustment in hospital discharge abstracts using data from 6 countries.

With advances in the effectiveness of treatment and disease management, the contribution of chronic comorbid diseases (comorbidities) found within the Charlson comorbidity index to mortality is likely to have changed since development of the index in 1984. The authors reevaluated the Charlson index and reassigned weights to each condition by identifying and following patients to observe mortality within 1 year after hospital discharge. They applied the updated index and weights to hospital discharge data from 6 countries and tested for their ability to predict in-hospital mortality. Compared with the original Charlson weights, weights generated from the Calgary, Alberta, Canada, data (2004) were 0 for 5 comorbidities, decreased for 3 comorbidities, increased for 4 comorbidities, and did not change for 5 comorbidities. The C statistics for discriminating in-hospital mortality between the new score generated from the 12 comorbidities and the Charlson score were 0.825 (new) and 0.808 (old), respectively, in Australian data (2008), 0.828 and 0.825 in Canadian data (2008), 0.878 and 0.882 in French data (2004), 0.727 and 0.723 in Japanese data (2008), 0.831 and 0.836 in New Zealand data (2008), and 0.869 and 0.876 in Swiss data (2008). The updated index of 12 comorbidities showed good-to-excellent discrimination in predicting in-hospital mortality in data from 6 countries and may be more appropriate for use with more recent administrative data.

When to initiate combined antiretroviral therapy to reduce mortality and AIDS-defining illness in HIV-infected persons in developed countries: an observational study.

BACKGROUND: Most clinical guidelines recommend that AIDS-free, HIV-infected persons with CD4 cell counts below 0.350 × 10(9) cells/L initiate combined antiretroviral therapy (cART), but the optimal CD4 cell count at which cART should be initiated remains a matter of debate. OBJECTIVE: To identify the optimal CD4 cell count at which cART should be initiated. DESIGN: Prospective observational data from the HIV-CAUSAL Collaboration and dynamic marginal structural models were used to compare cART initiation strategies for CD4 thresholds between 0.200 and 0.500 × 10(9) cells/L. SETTING: HIV clinics in Europe and the Veterans Health Administration system in the United States. PATIENTS: 20, 971 HIV-infected, therapy-naive persons with baseline CD4 cell counts at or above 0.500 × 10(9) cells/L and no previous AIDS-defining illnesses, of whom 8392 had a CD4 cell count that decreased into the range of 0.200 to 0.499 × 10(9) cells/L and were included in the analysis. MEASUREMENTS: Hazard ratios and survival proportions for all-cause mortality and a combined end point of AIDS-defining illness or death. RESULTS: Compared with initiating cART at the CD4 cell count threshold of 0.500 × 10(9) cells/L, the mortality hazard ratio was 1.01 (95% CI, 0.84 to 1.22) for the 0.350 threshold and 1.20 (CI, 0.97 to 1.48) for the 0.200 threshold. The corresponding hazard ratios were 1.38 (CI, 1.23 to 1.56) and 1.90 (CI, 1.67 to 2.15), respectively, for the combined end point of AIDS-defining illness or death. Limitations: CD4 cell count at cART initiation was not randomized. Residual confounding may exist. CONCLUSION: Initiation of cART at a threshold CD4 count of 0.500 × 10(9) cells/L increases AIDS-free survival. However, mortality did not vary substantially with the use of CD4 thresholds between 0.300 and 0.500 × 10(9) cells/L.

HTLV-I infection in the South West Indian Ocean islands, particularly in La Réunion and the Seychelles

Data on HTLV-I are scarce in several Southwest Indian Ocean islands except for La Réunion and The Seychelles. The two cases of HTLV-I have been confirmed by Western-Blot in La Réunion, among blood donors. In Seychelles (87 400 inhabitants in 2012), where blood donors and some other cases are screened, HTLV-I was confirmed with a line immune assay in 43 persons and at least 10-20 patients are known to have tropical spastic paraparesia or adult T-cell lymphoma associated with HTLV-I. In the south-west Indian Ocean, a possibly important other issue may be co-infection of HTLV-1 with the Strongyloides stercoralis roundworm, which is endemic in all countries of the region and which can sometimes lead to severe symptomatic infestation.

Malaria: une espèce en voie de disparition [Malaria: an endangered species?].

The implementation at scale of preventive measures and the use of effective treatments in populations living in endemic areas has led to a drastic reduction of the burden of malaria in all continents. The considerable investment of international agencies to support local governments in the fight against malaria allows hoping to achieve the millennium goals for malaria and child mortality in several countries. Malaria elimination, and even eradication becomes a realistic objective, especially so because a vaccine may be soon available to complement the armamentarium. For travelers, the tendency will be to reduce the number of countries where chemoprophylaxis or stand-by treatment is recommended and to insist on the rigorous use of measures to prevent mosquito bites such as repellents and insecticide-impregnated bednets.

Effects of victimization on the belief in a just world in four ex-Yugoslavian countries

Levels of support for just world beliefs among young adults (N = 598) from four ex-Yugoslavian countries-Bosnia and Herzegovina, Croatia, the former Yugoslav Republic of Macedonia, and Slovenia-were compared, taking into account victimization experiences and the general belief in a just world. Being a victim affected an individual's belief in a just world in the two less economically favored contexts: Victims of exclusion in Macedonia and victims of war in Bosnia and Herzegovina were less likely to believe in a just world than non-victims. These victimization variables partly explained why the mean scores of these two countries were less than those of the two others. A deleterious effect of cumulative negative events on belief in a just world was identified, in parallel with a lower endorsement of the belief when the first victimization occurred more recently.

The political economy of childcare in OECD countries : Explaining cross-national variation in spending and coverage rates

If childcare policy has become topical in most OECD countries over the last ten years or so, actual developments display huge cross-national variations. Countries like Sweden and Denmark spend around 2 per cent of GDP on this service, and provide affordable childcare places to most children below school age. At the other extreme, in Southern Europe, only around 10 per cent of this age group has access to formal daycare. Against this background, this article aims to account for cross-national variations in childcare services. It distinguishes two dependent variables: the coverage rate and the proportion of GDP spent subsidising childcare services. Using a mix of cross-sectional and pooled times-series methods, it tests a series of hypotheses concerning the determinants of the development of this policy. Its main conclusion for the coverage rate is that key factors are public spending and wage dispersion (both positive). For spending, key factors are the proportion of women in parliaments (positive) and spending on age-related policies (negative).

Seasonal variation of overall and cardiovascular mortality: a study in 19 countries from different geographic locations.

BACKGROUND: Cardiovascular diseases (CVD) mortality has been shown to follow a seasonal pattern. Several studies suggested several possible determinants of this pattern, including misclassification of causes of deaths. We aimed at assessing seasonality in overall, CVD, cancer and non-CVD/non-cancer mortality using data from 19 countries from different latitudes. METHODS AND FINDINGS: Monthly mortality data were compiled from 19 countries, amounting to over 54 million deaths. We calculated ratios of the observed to the expected numbers of deaths in the absence of a seasonal pattern. Seasonal variation (peak to nadir difference) for overall and cause-specific (CVD, cancer or non-CVD/non-cancer) mortality was analyzed using the cosinor function model. Mortality from overall, CVD and non-CVD/non-cancer showed a consistent seasonal pattern. In both hemispheres, the number of deaths was higher than expected in winter. In countries close to the Equator the seasonal pattern was considerably lower for mortality from any cause. For CVD mortality, the peak to nadir differences ranged from 0.185 to 0.466 in the Northern Hemisphere, from 0.087 to 0.108 near the Equator, and from 0.219 to 0.409 in the Southern Hemisphere. For cancer mortality, the seasonal variation was nonexistent in most countries. CONCLUSIONS: In countries with seasonal variation, mortality from overall, CVD and non-CVD/non-cancer show a seasonal pattern with mortality being higher in winter than in summer. Conversely, cancer mortality shows no substantial seasonality.

Gender and attachment representations in the preschool years: comparisons between five countries

Bowlby proposed that the individual's social experiences, as early as in infancy, contribute to the construction of Internal Working Models (IWMs) of attachment, which will later guide the individual's expectations and behaviors in close relationships all along his or her life. The qualitative, individual characteristics of these models reflect the specificity of the individual's early experiences with attachment figures. The attachment literature globally shows that the qualities of IWMs are neither gender specific nor cultural specific. Procedures to evaluate IWMs in adulthood have been well established, based on narrative accounts of childhood experiences. Narrative procedures at earlier ages (e.g., in the preschool years) have been proposed, such as Bretherton's Attachment Story Completion Task (ASCT), to evaluate attachment representations. More than 500 ASCT narratives of preschoolers, coming from five different countries, have been collected, in the perspective of examining possible interactions between gender and culture regarding attachment representations. A specific Q-Sort coding procedure (CCH) has been used to evaluate several dimensions of the narratives. Girls' narratives appeared as systematically more secure than those of same-age boys, whatever their culture. The magnitude of gender differences, however, varied between countries. Taylor's model of gender-specific responses to stress and Harwood's and Posada's hypothesis on inter-cultural differences regarding caregiving are evoked to understand the differences across gender and countries.

Lessons learned from developing a national NCD programme in low- and middle-income countries (Seychelles)

This paper identifies selected issues and lessons learned from the implementation of a national program of prevention and control of non-communicable diseases (NCD) during the past 20 years in the Seychelles, a small island state in the African region. As early as in 1989, population-based surveys demonstrated high levels of several cardiovascular risk factors, which prompted an organized response by the government. The early creation of a NCD unit within the Ministry of Health, coupled with cooperation with international partners, enabled incremental capacity building and coherent development of NCD programs and policy. Information campaigns and screening for hypertension and diabetes in work/public places raised awareness and rallied increasingly broad awareness and support to NCD prevention and control. A variety of interventions were organized for tobacco control and comprehensive tobacco control legislation was enacted in 2009 (including total bans on tobacco advertising and on smoking in all enclosed public and work places). A recent School Nutrition Policy prohibits the sale of soft drinks in schools. At primary health care level, guidelines were developed for the management of hypertension and diabetes (these conditions are managed in all health centers within a national health system); regular interactive education sessions were organized for groups of high risk patients ("heart health club"); and specialized "NCD nurses" were trained. Decreasing prevalence of smoking is evidence of success, but the raising "diabesity epidemic" calls for strengthened health care to high-risk patients and broader multisectoral policy to mould an environment conducive to healthy behaviors. Key components of NCD prevention and control in Seychelles include effective surveillance mechanisms supplemented by focused research; generating broad interest and consensus on the need for prevention and control of NCD; mobilizing leadership and commitment at all levels; involving local and international expertise; building on existing efforts; and seeking integrated, multi-disciplinary and multisectoral approaches.

The maritime shrew, Sorex maritimensis (Insectivora : Soricidae): a newly recognized Canadian endemic.

Previous morphological and cytological analyses have suggested that the arctic shrew (Sorex arcticus) as currently recognized may be two distinct species. Specifically, those studies demonstrated considerable differentiation between the putative subspecies S. a. maritimensis and one or both of the other two subspecies, S. a. arcticus and S. a. laricorum. Phylogenetic analysis of 546 base pairs of cytochrome b sequence data from 10 arctic shrews from across Canada indicates that maritimensis is the sister-group to arcticus + laricorum. Furthermore, there is considerable genetic divergence between maritimensis and the other two putative subspecies (similar to8-9%; Kimura's two-parameter distance). Given that maritimensis and arcticus + laricorum appear to be reciprocally monophyletic clades with considerable genetic divergence (i.e., greater than that between other recognized pairs of sister-species within the S. araneus-arcticus group), we propose that S. maritimensis be recognized as a distinct species. The proportion of third-position transversion substitutions between S. arcticus and S. maritimensis suggests that these two species shared a common ancestor approximately 2.4 million years ago.

Healthy, wealthy, wise, and happy? An exploratory analysis of the interplay between aging and subjective well-being in low and middle income countries

In this paper, we address the relationship between age and several dimension of subjective well-being. Whilst literature generally finds a U-shaped age-profile in subjective well-being, this age-pattern might only hold after controlling for objective life circumstances. The observed U-shaped age-profile might further not generalize to other dimensions of well-being and might vary across countries and cultures. Our study examines the relationship between age and several dimensions of well-being as well as the effect of objective life circumstances using the WHO Study on Global AGEing and Adult Health (SAGE). Our results suggest a decreasing age profile in the raw data associated with evaluative well-being, while experienced well-being shows a rather flat or slightly increasing pattern. However, age per se is not a cause of a decline in evaluative well-being. The negative age-profile in evaluative well-being is mainly explained by changes in life circumstances associated with aging. Controlling for socio-demographic factors, we find higher levels of well-being for older persons relative to their middle-aged counterparts. In contrast, we find that changes in life circumstances have a much smaller effect on experienced well-being.